Preheat oven to 350°. Spray a 17x12-inch rimmed baking sheet with baking spray with flour, and line bottom with parchment paper.
In the bowl of a stand mixer fitted with the paddle attachment, beat butter and sugar at medium speed until fluffy, 3 to 4 minutes, stopping to scrape sides of bowl. Add eggs, one at a time, beating well after each addition.
In a medium bowl, whisk together flour, cocoa powder, baking soda, and salt. With mixer on low speed, gradually add flour mixture to butter mixture alternately with buttermilk, beginning and ending with flour mixture, beating just until combined after each addition. Stir in food coloring, vinegar, and vanilla. Pour batter into prepared pan, and spread evenly using an offset spatula.
Bake until a wooden pick inserted in center comes out clean, 18 to 24 minutes, rotating halfway through baking. Let cool in pan for 10 minutes. Remove from pan, and let cool completely on wire racks. Place cooled cake on a cutting board, and refrigerate until chilled, about 3 hours.
Cut cake vertically in half, making sure cake halves are equal. Spread Cream Cheese Filling evenly on one layer, and top with remaining cake layer. Freeze until firm enough to cut, about 30 minutes. Using a serrated knife, gently trim edges of cake. Cut cake into about 1-inch squares.
In a medium microwave-safe bowl, heat chocolate and cream on high in 15-second intervals, stirring between each, until chocolate mixture is melted and smooth (about 1 to 1½ minutes). Spoon chocolate mixture into a piping bag and cut a ⅛-inch opening. Pipe chocolate ganache evenly over top of each cake bite. Top with holiday sprinkle mix. Refrigerate until set, about 20 minutes.
Notes
Kitchen Tip If you’re feeling extra festive, feel free to use Christmas shapes of cookie cutters to create fun star- or stocking-shaped versions of these yummy cake bites.
Recipe by Taste of the South at https://tasteofthesouthmagazine.com/red-velvet-cake-bites/